The present invention relates to a hand-held pliers for mounting purposes, especially for sliding sleeve tube connection systems wherein the pliers has two plier portions and a first pivot connection for pivotably connecting the two plier portions. Each plier portion comprises a jaw base body and a grip of a length that is a multiple of the length of the jaw base body. A first one of the grips is divided into a first section and a second section, whereby the first section is located between the jaw base body and the second section and is shorter than the second section. A second pivot connection for pivotably connecting the first section and the second section is provided. The second pivot connection comprises a pivot bolt extending parallel to a pivot axis of the first pivot connection. A sprocket wheel and a ratchet wheel with an outer toothing are rotatably connected to the pivot bolt. The sprocket wheel and the ratchet wheel are positioned axially adjacent to one another on the pivot bolt and are fixedly connected to one another. A chain having a first end connected to the second one of the grips is provided. A tension spring for connecting the second end of the chain to the second section of the first grip is provided. The chain is guided from the second grip across the sprocket wheel so as to be engaged by the sprocket wheel to the second section where the chain extends in the longitudinal direction of the second section toward the tension spring. A spring-biased follower pawl is connected to the second section such that upon a closing movement of the second section the sprocket wheel and the ratchet wheel perform a rotational movement resulting in a closure of the pliers.
A pliers of the aforementioned kind is known from German Patent 36 17 529. With the pivot mechanism in conjunction with the tensioning chain the clamping action provides for a much greater total transmission ratio and thus a correspondingly greater mounting force as compared to a conventional pliers with similar construction. When such a pliers is to be used for mounting non-metallic tube systems of relatively large diameters, correspondingly great mounting forces are required. In this context, due to the elasticity of the pliers and especially due to the unavoidable tolerances of the joint parts connected to one another, it is possible that during the clamping movement an elastic rebound may occur so that the follower pawl cannot engage the next tooth gap and a further increase of the clamping force is no longer possible.
It is therefore an object of the present invention to provide a pliers for mounting purposes with which even under extremely high mounting forces the pliers can be continuously closed without problems until the final position has been reached without experiencing elastic rebound.